JPS60261672A - Manufacture of structural member through molding padding andstructural member manufactured through said method - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is characterized in that a welding material is piled up to form a weld bead layer, and the structure of the weld bead layer is thermally heated one or more times when the structure of the weld bead layer piles up the following layer. The present invention relates to a method for manufacturing structural members from welding material by formed multilayer overlay welding.

Conventional technology Form welding is a known method of manufacturing structural parts entirely from welded materials, such as passages, bottoms, connecting pipe pieces and bent pipes for nuclear or chemical device fabrication. Products made of steel can be manufactured quickly and economically using the form-welding manufacturing process, with the highest material quality being met. Form welding is particularly suitable as a manufacturing method for structural members subjected to high stresses due to its isotropic material (4) properties and flexible formability.

In this case, highly productive mechanized welding methods are used, such as, for example, submerged arc welding, which has been widely proven in device fabrication. The essential advantages of producing structural parts by form welding are short production times, relatively low production costs and the possibility of integral construction without welded joints in factories and on construction sites. For components produced in this way, no heat treatment other than stress relief annealing is necessary, for example by tempering.

When welding a weld bead in layers using a single electrode or two electrodes placed one behind the other (tandem method) in the normal overlay welding method in submerged arc welding, we This results in the geometric surface of a mushroom with a flattened upper surface and a root extending downward in a drip-like manner. This weld bead shape results in a significant portion of the underlying weld bead being remelted, consuming energy (5). Furthermore, in the area below the heat-affected zone of the newly raised weld bead layer, some of the cast structure of the underlying weld bead layer is not sufficiently thermally influenced and therefore not transformed into the newly raised weld bead layer. The layer thermally converts a part of the previous layer into a relatively coarse structure in the area of the boundary layer.
Cast structure remnants and coarse-grained areas form in layers in the overlay material.

In particular, the stratified areas of cast-like and coarse-grained structures formed in the lower edge area of each weld bead are particularly important for welding, since the structure must be as fine-grained and homogeneous as possible in order to obtain sufficient toughness of the welding material. This causes quality deterioration regarding the toughness of the material.

Problems to be Solved by the Invention The problem on which the invention is based is that, in a method of manufacturing a structural member from a welding material by forming multilayer welding of the first type, the casting structure range and the coarse-grained structure The objective is to make improvements so that residual areas (6) are avoided and a welding material with only a fine grain structure is produced. Since the known method of producing structural parts by form welding requires a relatively high consumption of electrical energy for welding, the invention simultaneously improves the method by reducing the energy lost during remelting of the underlying layer. We are trying to improve economic efficiency. Simultaneously with achieving this objective, the operating capacity, ie the amount of welding material that can be pumped up per unit time for the same energy supply, must be increased as much as possible.

Means for Solving the Problem The solution to this task is, according to the invention, in a method for producing structural parts from welding material by form overlay welding of the first mentioned type, in which the underlying m-layers are Advantageous melting associated with the material is achieved by embellishing the bead layer so that the area is completely transformed into areas of fine-grained structure and the structural member has a homogeneous fine-grained structure with isotropic properties. be done.

(7) When choosing the bead geometry as a flat weld bead with a lenticular cross-section, the conversion of the heat-affected zone is carried out in such a way that it causes a complete granular reconversion of the structure into the previous structure layer. is advantageous.

According to another configuration, the weld bead layer is dimensioned such that the weld pool depth is equal to or less than the sum of the penetration depth and the depth of the granular heat-affected zone, so that the structural component has a completely homogeneous fine grain structure.

According to a further development, it is advantageous if the weld bead layer is configured with a shallowly extending root area.

In order to obtain a predetermined bead shape advantageously and simply, it is proposed according to the invention that an electrode arrangement is used which ensures a lenticular flat bead shape instead of a mushroom-like bead shape.

According to a further development of the invention, a very advantageously simple construction is obtained in that flat metal strips are used as electrodes.

(8) As electrodes it is possible to use strips or a plurality of single electrodes, for example wire electrodes, which are guided transversely and parallel to the direction of motion. In order to facilitate the formation of a homogeneous fine-grained structure in the welding material, which is the object of the invention, the invention further provides that the structural component is kept at an elevated temperature during overlay welding in a known manner. It is proposed to let the fibers sag, and this temperature allows the most advantageous braiding to obtain high tenacity and strength properties.

Structural elements produced from welding material by shaped multilayer welding, in which the welding material is constructed in successive weld bead layers, are produced in a method according to the claims and have isotropic properties. It differs from similar parts manufactured by the prior art in that it has a homogeneous fine-grained structure with a .

This structural component with a homogeneous fine-grained structure is characterized in that it is particularly suitable to be manufactured from a welding material whose material quality corresponds to steel quality 10 MnMoN155.

(9) Embodiment The invention is shown in a schematically illustrated embodiment compared to the prior art, from which advantageous details of the invention can be seen.

In the prior art weld bead according to FIG. 1, weld pool depth S1 penetration depth E1 coarse grain zone depth G1 fine grain zone depth F
A cross-sectional shape having an unspecified dimensional relationship between the build-up thickness and the build-up thickness A is obtained.

This results in unspecified grain transformation conditions when welding multiple bead layers one on top of the other, and the resulting weld material has a range of textures that vary from layer to layer, i.e. unconverted cast texture (hatched), coarse-grained It consists of a structure that has been converted into fine grains (black area) and a structure that has been converted into fine grains (dot area).

As a welding example of the present invention, FIG. 3 shows S, E, and G.

4 shows a modified cross-sectional shape of an individual bead with a defined dimensional relationship of F and A, which cross-sectional shape
As schematically illustrated in FIG. 5 and FIG. 5, the superposition of multiple weld bead layers results in a complete micro-(10) grain structure transformation in the underlying weld material.

Since the setting of S, E, F, G and A in order to satisfy the conditions shown in FIG. to optimally accomplish the task initially assigned.

When selecting the welding parameters in relation to the 8 materials, care must be taken that the following relationships according to FIG. 5 are fulfilled:

S < E 10F F≧5−F FnA A>G Emin == S -F Emax = 5-G

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view showing the dimensions of a weld bead according to the prior art, FIG. 2 is a schematic cross-sectional view of three overlapping weld beads according to the prior art, and FIG. 3 is a schematic cross-sectional view showing the dimensions of a weld bead according to the present invention. 4 is a schematic cross-sectional view of three overlapping weld beads according to the invention, and FIG. 5 is a schematic view illustrating, for example, determination of penetration depth according to the invention. Continuing from page 1 of Shaft [Co., Ltd.] Inventor: Ratan Datsuk Toytra 0 Inventor: Horst Twinmel Toyman - Federal Republic of Seso Oberhausen 11, Elstnerschusse 26 Republic of the Soviet Union Oberhausen 14, Gertilstra 11

Claims (1)

[Claims] l The welding material is raised to form a weld bead layer, and the W
1 when the structure of the g-contact bead layer bulges the subsequent layer.
A method of manufacturing structural members from welded material by forming multilayer welding, which is thermally converted once or more times, in which the underlying texture is completely transformed into areas of fine-grained structure and the structural member is homogeneous. Advantageous welding and doping shapes related to the material, such as having a fine-grained structure, weld pool depth, penetration depth, underlying coarse-grained texture areas or fine-grained textures characterized in that the depth of the area is defined;
A method of manufacturing structural members from welded materials by forming multilayer overlay welding. 2. The individual weld beads are dimensioned such that the weld pool depth is less than or equal to the sum of the penetration depth and the fine grain zone depth. The method described in. 3. Claim 1, characterized in that the build-up thickness of the individual weld bead is kept equal to or less than the depth of the fine-grained zone and equal to or greater than the depth of the coarse-grained zone.
The method described in Section 1 or Section 2. 4. Claim 1, characterized in that the minimum seepage depth is equal to the difference between the weld pool depth and the fine grain zone depth, and the maximum slang depth is equal to the difference between the weld pool depth and the coarse grain zone depth. The method according to one of paragraphs 3 to 3. 5. Method according to one of claims 1 to 4, characterized in that the bath contact bead layer is constructed with a shallowly extending root area. 6. Method according to one of claims 1 to 5, characterized in that a flat metal strip is used as the electrode. 7. In accordance with one of the claims 1 to 6, characterized in that a plurality of single electrodes are used as electrodes, which are guided in two horizontal rows transversely to the direction of motion. Method described. 8. Method according to one of claims 1 to 7, characterized in that the structural component is kept at an elevated temperature during overlay welding. 9. In structural parts produced from welding material by formed multilayer welding, in which the welding material is constructed in successive weld bead layers, the underlying texture is completely converted into areas of fine-grained structure and In order for the structural member to have a homogeneous fine-grained structure, the advantageous weld bead shape, weld pool depth, and penetration depth related to the material, the underlying texture area converted to coarse-grained or fine-grained The welding material is built up in a weld bead layer, and the structure of the weld bead layer is thermally transformed one or more times during the buildup of subsequent layers. A structural member characterized in that the structural member is manufactured by a method of manufacturing a welding material from a welding material by multi-layer overlay welding, and has a homogeneous machine (3) grain structure. 10. Structural element according to claim 9, characterized in that it is produced from a welding material whose material quality corresponds to a steel quality of 10 MnMoNj 55.